<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>北大青鸟宣传片</title>
	</head>
	<body>
		<video controls loop>
			<source src="bd.mp4 " type="video/mp4" />
 			<source src="bd.webm" type="video/webm"/>
	
		</video>
	</body>
</html>
